1. Field of the Invention
The present invention relates to a display device, and more particularly to a technique which is effectively applicable to a display device which transfers digital signals between drive circuits.
2. Description of the Related Art
A TFT (Thin Film Transistor)-method liquid crystal display module which adopts thin film transistors as active elements has been popularly used as a display device of a personal computer and the like. Such a liquid crystal display device includes a liquid crystal display panel and drive circuits for driving the liquid crystal display panel.
Further, in such a liquid crystal display module, for example, as disclosed in patent document JP-A-2001-306040, there has been known a method (hereinafter, referred to as a digital-signal sequential transfer method) which supplies digital signals (for example, display data or a clock signals) only to a start drive circuit out of drive circuits (drain drivers or gate drivers) which are connected with each other by cascade connection and sequentially transfers the digital signals to other drive circuits through the inside of the drive circuits.
In a liquid crystal display device disclosed in JP-A-2001-306040, semiconductor chips (IC) which constitute drive circuits (drain drivers or gate drivers) are directly mounted on a substrate (for example, glass substrate) which constitutes a liquid crystal display panel. Further, power source voltages of the respective drain drivers are supplied from a power source circuit via a flexible circuit board which is connected to the liquid crystal display panel.